This invention is related to an improved and efficient process for the large-scale isolation of (-)-hydroxycitric acid or Garcinia acid (2S,3S-dihydroxy 1,2,3-propanetricarboxylic acid) from fresh or dried rinds of the fruits of Garcinia cambogia, Garcinia indica and Garcinia atroviridis. Garcinia acid is widely used as an important ingredient in many pharmaceutical formulations.